Final answer:
Astronauts may experience muscle atrophy, vision changes, and radiation exposure after returning home from space travel.
Step-by-step explanation:
Astronauts may experience several health concerns after returning home from space travel. One of the main concerns is muscle atrophy, which refers to the loss of muscle mass and strength due to the lack of gravity in space. Without regular exercise and resistance training, muscles can weaken and decrease in size. Another health concern is vision changes, as long-duration space travel can cause pressure changes in the eyes and affect visual acuity. Lastly, radiation exposure is a significant health risk in space, as astronauts may be exposed to high-energy solar radiation, which can increase the risk of cancer and other radiation-related illnesses.